20 research outputs found
Reversible Holmes Tremor due to Middle Cerebral Artery Giant Aneurysm
A 40-year-old man presented with a 6-month history of mild but worsening tremor of variable intensity. The patient had a focal, irregular, rest and action tremor of middle amplitude and low frequency (about 4 Hz), limited to his right arm with oscillatory motion around the elbow. It was present inconsistently at rest, particularly during emotional activation, and enhanced by posture maintenance. It was evoked by various positions and tasks. Particularly, the tremor was present during fine motor skills such as writing, and it was increased by drinking and shaving, showing a minimal intentional component. The patient also reported slight loss in manual dexterity in his right hand
Centrin 2: a novel marker of mature and neoplastic human astrocytes
As microtubule organizing centers, centrosomes play a pivotal role in cell division as well as in neurodevelopment and neuronal maturation. Among centrosomal proteins, centrin-2 (CETN2) contributes also to DNA repair mechanisms which are fundamental to prevent genomic instability during neural stem cell pool expansion. Nevertheless, the expression profile of CETN2 in human neural stem cells and their progeny is currently unknown.
To address this question, we interrogated a platform of human neuroepithelial stem (NES) cells derived from post-mortem developing brain or established from pluripotent cells, and demonstrated that while CETN2 retains its centrosomal location in proliferating NES cells, its expression pattern changes upon differentiation. In particular, we found that CETN2 is selectively expressed in mature astrocytes with a broad cytoplasmic distribution. We then extended our findings on human autoptic nervous tissue samples. We investigated CETN2 distribution in diverse anatomical areas along the rostro-caudal neuraxis and pointed out a peculiar topography of CETN2-labelled astrocytes in humans which was not appreciable in murine tissues, where CETN2 was mostly confined to ependymal cells. As prototypical condition with glial overproliferation, we also explored CETN2 expression in glioblastoma multiforme, reporting a focal concentration of CETN2 in neoplastic astrocytes.
This study expands CETN2 localization beyond centrosomes and reveals a unique expression pattern which makes it eligible as a novel astrocytic molecular marker, thus opening new roads to glial biology and human neural conditions
Assessment of plaque morphology in alzheimer’s mouse cerebellum using three-dimensional X-ray phase-based virtual histology
Visualization and characterization of beta -amyloid deposits is a fundamental task in pre-clinical study of Alzheimer's disease (AD) to assess its evolution and monitor the efficiency of new therapeutic strategies. While the cerebellum is one of the brain areas most underestimated in the context of AD, renewed interest in cerebellar lesions has recently arisen as they may link to motor and cognitive alterations. Thus, we quantitatively investigated three-dimensional plaque morphology in the cerebellum in APP/PS1 transgenic mouse, as a model of AD. In order to obtain a complete high-resolution three-dimensional view of the investigated tissue, we exploited synchrotron X-ray phase contrast tomography (XPCT), providing virtual slices with histology-matching resolution. We found the formation of plaques elongated in shape, and with a specific orientation in space depending on the investigated region of the cerebellar cortex. Remarkably, a similar shape is observed in human cerebellum from demented patients. Our findings demonstrate the capability of XPCT in volumetric quantification, supporting the current knowledge about plaque morphology in the cerebellum and the fundamental role of the surrounding tissue in driving their evolution. A good correlation with the human neuropathology is also reported
Life during COVID-19 lockdown in Italy: the influence of cognitive state on psychosocial, behavioral and lifestyle profiles of older adults.
Few studies have examined lockdown effects on the way of living and well-being of older adults stratified by cognitive state. Since cognitive deficits are common in this population, we investigated how cognition influenced their understanding of the pandemic, socio-behavioral responses and lifestyle adaptations during lockdown, and how these factors affected their mood or memory.Telephone-based survey involving 204 older adults ≥65 y/o (median: 82) with previous assessments of cognitive state: 164 normal-old (NOLD), 24 mild-neurocognitive disorder (mild-NCD), 18 mild-moderate dementia. A structured questionnaire was developed to assess psychological and socio-behavioral variables. Logistic regression was used to ascertain their effects on mood and memory.With increasing cognitive deficits, understanding of the pandemic and the ability to follow lockdown policies, adapt to lifestyle changes, and maintain remote interactions decreased. Participants with dementia were more depressed; NOLDs remained physically and mentally active but were more bored and anxious. Sleeping and health problems independently increased the likelihood of depression (OR: 2.29; CI: 1.06-4.93;NOLD and mild-NCD groups showed similar mood-behavioral profiles suggesting better tolerance of lockdown. Those with dementia were unable to adapt and suffered from depression and cognitive complaints. To counteract lockdown effects, physical and mental activities and digital literacy should be encouraged
The expression pattern of GDF15 in human brain changes during aging and in Alzheimer's disease
Introduction: Growth Differentiation Factor 15 (GDF15) is a mitochondrial-stress-responsive molecule whose expression strongly increases with aging and age-related diseases. However, its role in neurodegenerative diseases, including Alzheimer's disease (AD), is still debated. Methods: We have characterized the expression of GDF15 in brain samples from AD patients and non-demented subjects (controls) of different ages. Results: Although no difference in CSF levels of GDF15 was found between AD patients and controls, GDF15 was expressed in different brain areas and seems to be predominantly localized in neurons. The ratio between its mature and precursor form was higher in the frontal cortex of AD patients compared to age-matched controls (p < 0.05). Moreover, this ratio was even higher for centenarians (p < 0.01), indicating that aging also affects GDF15 expression and maturation. A lower expression of OXPHOS complexes I, III, and V in AD patients compared to controls was also noticed, and a positive correlation between GDF15 and IL-6 mRNA levels was observed. Finally, when GDF15 was silenced in vitro in dermal fibroblasts, a decrease in OXPHOS complexes transcript levels and an increase in IL-6 levels were observed. Discussion: Although GDF15 seems not to be a reliable CSF marker for AD, it is highly expressed in aging and AD brains, likely as a part of stress response aimed at counteracting mitochondrial dysfunction and neuroinflammation
Expression pattern of perilipins in human brain during aging and in Alzheimer's disease
Aims: Perilipins are conserved proteins that decorate intracellular lipid droplets and are essential for lipid metabolism. To date, there is limited knowledge on their expression in human brain or their involvement in brain aging and neurodegeneration. The aim of this study was to characterise the expression levels of perilipins (Plin1-Plin5) in different cerebral areas from subjects of different age, with or without signs of neurodegeneration. Methods: We performed real-time RT-PCR, western blotting, immunohistochemistry and confocal microscopy analyses in autoptic brain samples of frontal and temporal cortex, cerebellum and hippocampus from subjects ranging from 33 to 104 years of age, with or without histological signs of neurodegeneration. To test the possible relationship between Plins and inflammation, correlation analysis with IL-6 expression was also performed. Results: Plin2, Plin3 and Plin5, but not Plin1 and Plin4, are expressed in the considered brain areas with different intensities. Plin2 appears to be expressed more in grey matter, particularly in neurons in all the areas analysed, whereas Plin3 and Plin5 appear to be expressed more in white matter. Plin3 seems to be expressed more in astrocytes. Only Plin2 expression is higher in old subjects and patients with early tauopathy or Alzheimer's disease and is associated with IL-6 expression. Conclusions: Perilipins are expressed in human brain but only Plin2 appears to be modulated with age and neurodegeneration and linked to an inflammatory state. We propose that the accumulation of lipid droplets decorated with Plin2 occurs during brain aging and that this accumulation may be an early marker and initial step of inflammation and neurodegeneration
Dementia and Risk Factors: Results from a Prospective, Population-Based Cohort Study
The incidence rate of dementia varies between studies. The influence of some sociodemographic factors is reasonably established, but less is known about the role of comorbidities, which are common in the elderly. The objectives of this study was to estimate the incidence of dementia in a population of Italian elders and evaluate the role of walking speed, comorbidity and ApoE-ɛ4 as well as various sociodemographic factors on the new onset of dementia. The InveCe.Ab study is a population-based longitudinal study in people born between 1935 and 1939 and resident in Abbiategrasso, Milan, Italy. After excluding subjects with a diagnosis of dementia and those without a definite diagnosis, 1103 individuals with a median follow-up time of 4.1 years were included in the analyses. The cumulative four-year incidence of dementia was 5.3%. Demographic factors such as old age, male, less educated, ApoE-ɛ4 carrier status and slower gait were risk factors for dementia onset in a cognitively healthy sub-cohort. Comorbidity did not influence the onset of dementia; instead, slow walking speed appears to be a strong predictor of dementia onset
Good outcome in adult-onset Rasmussen's encephalitis syndrome: is recovery possible?
A healthy 29-year-old man suffered from adult-onset epilepsy, characterized by polymorphic progressive seizures resistant to AEDs, leading to unilateral cortical deficits and atrophy of the left hemisphere. The disorder satisfied the clinical, EEG, and imaging criteria for a diagnosis of Rasmussen's encephalitis. During the acute phase of the disease, intrathecal synthesis of specific anti-CMV IgG was identified. This case was characterized by a very mild course and remission of seizures following a treatment with high-dose intravenous polyvalent immunoglobulins containing a high anti-CMV titre. The patient remained symptomless for more than 15 years from clinical onset and more than eight years after the discontinuation of immunological therapy. In agreement with a recent report, this case confirms that adult-onset Rasmussen's encephalitis syndrome may occur with a very mild clinical picture and persistent remission. In this case, the specific index for intrathecal production of anti-CMV antibodies suggested possible CMV involvement, indicating specific immuno-therapy as a treatment choice
From brain collections to modern brain banks: A historical perspective
Our current knowledge of the structure, function, and diseases of the brain comes from direct examination of its substance. In the last centuries, only a few elite had managed to retrieve, gather, and preserve the elusive brain for their own research. The resulting brain collections, stored in formalin-filled jars or dried up in cabinets, served anatomical, neuropathological, anthropometric, ideological, and diagnostic purposes. In the 1960s, the first modern brain banks actively collecting and strategically preserving both diseased and healthy brains to be consequently distributed to the scientific community were instituted. In an era where state-of-the-art biochemical "Omic" studies and advanced metabolic and molecular neuroimaging exist, it is now, more than ever, that postmortem brain investigations must be performed. Only through the comparison and integration of postmortem neuropathological and biochemical findings and antemortem data from clinical, neuropsychological neuroimaging, and other biomarker examinations can we truly understand neurological disease mechanisms. Brain banks supplying brain specimens, antemortem information, and postmortem diagnosis are a major benefactor of brain research